The articulating joint is a complex system that is regularly subjected to trauma, inflammatory and metabolic processes. More than 20 million individuals in the United States have symptomatic osteoarthritis and suffer from some debilitation of the joints and therefore developing interventive and regenerative medical cures is a national priority. Our projects are aimed at gaining a greater understanding of the development of bone/cartilage interfaces for the reconstruction of articular joints such as the temporomandibular joint (TMJ). The long-term objective of this proposal is to develop strategies to regenerate multi-tissue interfaces with a focus on the bone-cartilage interface. We propose a hypothesis and design-driven tissue engineering project based on rapid fabrication of bioengineered scaffolds, with custom-tailored surface chemistry, that control the spatial and temporal release of bioactive factors to regenerate the bone and cartilage interface. The controlled generation of this interface will be directed via an in vivo regenerative gene therapy approach. The central hypothesis is that delivery of bioactive signaling factors (BMP-2 and Sox9) to distinct regions of designed scaffolds can control the lineage commitment of responsive cells to develop a bone/cartilage interface. 1. To custom-tailor the surface chemistry of biomaterials with precisely designed biological signaling properties. Poly 5-caprolactone (PCL) surfaces will be modified by chemical vapor deposition (CVD) to establish surface coatings with a variety of polymer properties and conjugation chemistries. Three different immobilization models will be developed in this specific aim to gain maximal control of viral release through a dynamic equilibrium of biotin/avidin and biomaterial interactions. 2. To immobilize two different viruses on a single scaffold to control delivery of specific biological signaling factors and to understand how these signals control the development of a biological interface. Material surfaces will be modified to control the delivery of multiple adenoviruses. Two-way CVD will also be used to generate signaling gradients to mimic natural developmental signaling patterns at an interface. 3. To develop a bone-cartilage interface by directing the lineage progression of responsive cells to bone and cartilage using in vivo regenerative gene transfer strategies on designed biomaterial scaffolds. Tissue interfaces will be generated on biomaterial scaffolds in vivo. The precision of interface development will be studied by delivering BMP-2 on one region of a scaffold and antagonists such as noggin or dominant negative BMP receptors on the adjacent surfaces. The development of bone/cartilage interfaces will be studied in vivo by the controlled delivery of BMP-2 (bone) and Sox-9 (cartilage). PUBLIC HEALTH RELEVANCE: When congenital anomalies, traumatic injuries or inflammatory and degenerative diseases involve an articulating joint such as the temporomandibular joint (TMJ), the effects are often physically, financially and emotionally debilitating. Unfortunately, despite decades of targeted clinical and basic science research, well established methods to repair or regenerate such joints remain elusive, resulting in a significant unmet clinical need. The long-term objective of this proposal is to develop strategies to regenerate the bone-cartilage interface to regenerate joins like the TMJ.